Digital video cameras are useful in both consumer and professional contexts. Generally, digital video cameras capture sequences of digital images, which may then be transferred to a computer system for display or processing or to a storage device for storage.
One specific practice employs a digital video camera in a video conferencing application. In a typical video conference, an image sequence depicting a conference participant is transmitted to one or more other participants. Concurrently, image sequences depicting the other participants are transmitted to the first participant's display device. In this manner, each participant can view an interactive video of the other participants during the conference.
In a typical video teleconferencing environment, a single video camera is focused on a conference participant, who views the other participants in a video window in his or her display device. The video camera is commonly mounted on or near the display of a computer or television system in an attempt to minimize the angle between the camera and the video window. Minimizing this angle can enhance the illusion that the participant is looking into the camera instead of at the video window in the display device. However, the angle is never really eliminated and in fact can remain significant, particularly when the camera is close to the participant. As a result, for example, the other participants receive a display of the top or side of the first participant's head, instead of a straight-on view of the first participant's face.
This situation provides a diminished user experience and limits the effectiveness of such video conferencing. It is difficult to develop trust between participants in the conference because of the difficulty in establishing eye contact (i.e., the displayed participant is looking at his or her display instead of the camera). Likewise, facial expressions may be distorted or obscured by the angular discrepancy, thereby losing some important communication cues.
Conceptually, these problems may be resolved by a physical camera positioned in the center of the display window, such that the participant's focus and the camera's focus are aligned—envision a video display with a hole drilled in the middle of it in which to mount the camera. However, such configurations are impractical for obvious reasons.